Liquefied gas propellant compositions



Nov. 7, 1950 F. G. LODES 2,529,092

LIQUEFIED GAS PRQPELLANT COMPOSITIONS Filed Nov. 26; 1948 VAPOR PRESSURE p.5./. 1. AT 70"/-'.

5 IO /5 2O 4O 5O PERCENT CCI F INVENTOR. FREDERICK G. LODES ATTORNEY.

Patented Nov. 7, 1950 UNITED 1 STATES PATENT OFFICE LIQUEFIED GAS PROPELLANT f COMPOSITIONS Frederick G. Lodes, Yonkers, N. Y., assignor to Allied Chemical & Dye Corporation, New York, N. Y., a corporation of New York Application November 26, 1948, SerialNo. 61,999

8 Claims. (01. 252-a) i 1 1 This invention relates to non-flammable, nontoxic liquefied gas compositions, adapted for use as dispersants, and particularly for 'use in the mum for low pressure dispersants being set by current governmental regulations. Of the two groups, low pressure dispersants have become of increasing greater commercial importance because their low pressure characteristics are essential features of the dispersants used in the production of low pressure aerosol bombsnow employed widely particularly for household purposes. The principal requirements for a low pressure dispersant are that it possesses nonflammable and non-toxic properties, has a. vaporpressure appreciably below 40 p. .s. i. g. at room temperature, and that it be of such composition as to contain a relatively large amount of dispersant material which is volatile, and exists as a gas at room temperature.

Two compounds used in admixture toa substantial commercial extent in the low pressure dispersant field are dichlorodifluoromethane (CClzFz) and trichlorofiuoromethane (CClsF). The former bolls at minus 292 C. and has a vapor pressure at room temperature of about 70 p. s. i. g., while trichlorofiuoromethane boils at 23.9" C. but has no effective vapor pressure at room temperature. Both compounds are nonflammable and non-toxic, and hence mixtures of such materials satisfy these two major requirements. However, the room temperature vapor pressure of dichlorodifluoromethane is much too high to permit use of this compound aloneas a low pressure dispersant. Hence, it has been the practice to formulate various mixtures of dichlorodifiuoromethane and trichlorofiuoromethane in proportions such that the vapor pressure at room temperature of such mixtures is low enough to permit use as a low pressure dispersant. The only part of these dispersant mixtures which is an active ingredient in an aerosol sense is the volatile matter content, i. e. the dichlorodifiuorometh ne const tllcm which is a gas at room temperature. In the aerosol dispersant art and in the present specification and claims, the expression volatile matter? designates constituents which existas gasesat room temperature. Thus in commercial mixtures of trichlorofiuoromethane and dichlorodifiuoromethane, the only volatile matter material is the dichlorodifluoromethane, the trichlorofluoromethane is non-volatile and functions primarily as a pressure depressant.

The higher the volatile matter content of an aerosol dispersant, the more desirable is the dispersant for the purposes indicated. In commercial mixtures of trichlorofiuoromethane and dichlorodifluoromethane, in order to bring down 7 the room temperature vapor pressure to or below the current allowable maximum of 40 p. s. i. g., it is necessary to incorporate a relatively large quantity of trichlorofluoromethane. The greater the amount of trichlorofluoromethane, the less is the permissible maximum of the volatile dichlorodifiuoromethane. For example, in a representative commercial dichlorodifluoromethanetrichlorofiuoromethane mixture, sufficient trichlorofluoromethane is utilized to bring the room temperature vapor pressure of the mixture down to about 36 p. s. i. g., the latter valuebeing adopted to provide a relatively large factor of safetyin the filling of the aerosol containers commonly referred to in the lower pressure field as the beer can type. A mixture of the foregoing nature contains by weight about 50% trichlorofiuoromethane and dichlorodifluoromethane, and it will be seen that in order to provide a dispersant having a given vapor pressure, the volatile matter content of the mixture is limited, i. e. as instanced, to a maximum of 50% of the total composition. Insome circumstances-the vapor pressure of a low pressure dispersant might be raised to say 37-39 p. s. i. g., in which situation, the dichlorodifiuoromethane volatile matter content may be increased to some small extent. However, such volatile matter increase is so small as to be of little practical importance. 0n the other hand, it will be understood that in the manufacture of dispersants having vaporpressures at room temperature decreasingly less than say 36 p. s. i. g., it is necessary to progressively increase the trichlorofiuoromethane content in order to bring down the pressure, the result be:- ing a corresponding decrease of the volatile matter content of the lower pressure mixtures.

The object of this invention is to provide low pressure, liquid dispersant compositions which are non-flammable, non-toxic, and have volatile matter contents which are greater than the volatile matter contents of prior commercially employed low pressure dispersants, e. g. mixtures of dichlorodifiuoromethane and trichlorofiuoromethane, having corresponding room temperature vapor pressure values. Further, the invention aims to afford liquid dispersant compositions which because of their non-flammable, nontoxic, and high volatile matter content characteristics are especially adapted for use in the manufacture of low pressure insecticidal aerosols suitable particularly for household purposes.

According to this invention, it has been found that the incorporation into amixture of dichlorodifiuoromethane and trichlorofiuoromethane of any amount of 1,1,1-difiuorochloroethane (CH3CC1F2) provides a low pressure dispersant which has, for any given or required vapor pressure, a higher volatile matter content than the" volatile matter content of mixtures of dichlorodifluoromethane and trichlorofluoromethane having the same vapor pressure value. The 1,1,1- difiuorochloroethane is a non-toxic,slightly flammable material boiling at minus 9.2 C., and having a vapor pressure of 30.2 p. s. i. g. and a specific gravity of 1.12 at 70 F. This material exists as a gas at room temperature, and hence in the aerosol sense is volatile matter. I find that the inherent properties of 1,1,l-difluoroch1oroethane are such that so great an amount of 1,1,1difiuorochloroethane may be incorporated into mixtures of dichlorodifluoromethane and trichlorofluoromethane as to result in the forand dichlorodifluoromethane.

mation of low pressure di persants having volatile matter contents which are substantially higher than the highest permissible volatile mixtures of dichlorodifluoromethane and tri-.

chlorofluoromethane as to result in the forma' tion of low pre sure di persants containing preferably and more by weight of 1,1,1-difluoro chloroethane, and having low effects, and having volatile matt r contents,

preferabl not less than by weight, far in excess of the highest possible volatile matter content of commercially feasible dichlorodifluoromethane-trichlorofluoromethane mixtures having vapor pressures at or below 40 p. s. i. g.

at F.

The compositions of the invent on con ist of 1,1,1 difluorochloroethane, dichlorodifluorb methane, and trichlorofluoromethane. The relative proportioning of these materials depends upon sought-for characteristics, principally vapor pressure and volatile matter content of the finished products. In their broader aspects, the improved dispersant compositions consist of the three compounds indicated, and contain by weight not less than about 15% and not more than about 76%,? of 1,1,1-difluorochloroethane, not more than about 45% and not less than about 5% of dichlorodifiuoromethane, the remainder, to provide a 100% composition, being trichlorofluoromethane. In these compositions, it will be understood that, for any given vapor pressure, the greater the 1,1,1-difiuorochloroethane content, the less are the amounts of dichlorodifiuoromethane and. t chlorofluoromethane.

distillation All of the compositions included in the stated content ranges are so constituted as to have vapor pressures in the range of about 18-l9 to about 40 p. s. i. g. at 70 F. In making up compositions containing as little as about 15% by weight of 1,1,1-difiuorochloroethane, such composition should contain not more than about 45% dichlorodifluoromethane in order to keep the vapor pressure at 70 F. at about or below 40 p. s. i. g. In this instance, the trichlorofluoromethane content is about e0%, it being noted that in this particular composition the total volatile matter content of 1,1,1-difiuorochloroethane and dichlorodifiuoromethane is about 60%. In this specification and appended claims,

, the expression total volatile matter designates the total weight of 1,1,1-difluorochloroethane When making up a composition containing about 76% 1,1,1-difiuorochloroethane, the dichlorodifiuoromethane content may be reduced to as low as about 5%, in which case the trichlorofluoromethane' content is about 19%, the proportioning of ingredients in this circumstance being such as to provide a product having at 70 F. a Vapor pressure of the order of 31-32 p. s. i. g., and a total volatile matter content of 1,1,1-difluorochloroethane and dichlorodifiuoromethane of about 81%.

In accordance with the invention it has been found that when 1,1,1-difluorochloroethane, dichlorodifluoromethane and trichlorofiuoromethane are utilized in quantities lying within the stated ranges and when the amounts of l,1,ldifluorochloroethane and trichlorofluoromethane are chosen, within the indicated ranges, so that the resulting composition has a total volatile matter content of 1,1,l-difiuorochloroethane and dichlorodifiuoromethane of not less than about 40% and not more than about by weight, there are formed compositions having a vapor pressure in the range of about 18-19 to about 40 p. s. i. g. at 70 F., and containing substantially greater amounts of volatile matter than do mixtures of dichlorodifiuoromethane and trichlorofiuoromethane having corresponding pressure values. Thus, forany'given vapor pressure, the volatile matter contents of all products of the invention are substantially greater than, and in the preferred embodiment far in excess of, the volatile matter content of a mixture of trichlorofiuoromethane and dichlorodifiuoromethane having the same vapor pressure. It is noted that the total volatile matter content of products of the invention should not exceed about 95% in order to maintain vapor pressures at 70 F. about or below 40 p. s. i. g.

The diagram on the accompanying drawing illustrates composition-vapor pressure at 70 F. relationships of products falling within the scope of the invention. Diagonal lines I, 2, 3, t, 5, and 6 indicate compositions respectively containing 15%, 20%, 30%, 40%, 50%, and 76% by weight of 1,1,l-difluorochloroethane. While the variable range of dichlorodifluoromethane content is designated, the amounts of trichlorofiuoromethane contained in the compositions are bounded by the straight lines connecting the between lines I and 6 contain 1,1,1-difluorochloroethane in amount ranging from about 15% to about 76 by weight, and all such compositions lying to the left of the vertical passing thru the H! and to the right of vertical line l2-l'| contain dichlorodifluoromethane in the range of 45-5% by weight. It will be observed that the specific composition indicated at H contains about 15% 1,1,1-difiuorochloroethane and about 25% dichlorodifiuoromethane, the total volatile matter content being the sum of the two, i. e. 40%. Similarly, e. g. the specific composition at l6, contains about 30% 1,1,1-difluorochloroethane and about dichlorodifluoromethane, and has a total volatile matter content of about 40% Thus, all compositions lying above line l|-!2 contain not less than about 40% by weight of volatile matter. The particular composition at 18 contains about 76% 1,1,1-difluorochloroethane and about 19% dichlorodifiuoromethane, and accordingly has a volatile matter content of about 95%, which value as previously noted should not be exceeded in order to maintain vapor pressure at 70 F. not significantly above 40 p. s. irg. As shown, all of the products thus far described have vapor pressures at 70 F. in the range of about l8-19to about 40 p. s. i. g.

Depending upon the desired 70 F. vapor pressure of any particular sought-for product falling within the broader aspects of the invention, the composition of such product may be determined and made up obviously by inspection and interpolation of the chart. 7 Since an important feature of the invention lies in provision of relatively high volatile matter content compositions, it is desirable in the formulation of the improved products to utilize amounts of 1,1,l-difluorochloroethane and dichlorodifiuoromethane within the outside ranges denoted such that the resulting compositions have a total volatile matter content of 1,1,1-difluorochloroethane and dichlorodifluoromethane of not less than 55% and not more than 95% by weight. Referring again to the drawing, the specific product indicated at 20 contains about 1,1,1- difiuorochloroethane and about 40% dichlorodifluoromethane, the total volatile matter content being about 55%. The specific product at [3 contains about 50% 1,1,1-difluorochloroethane and about 5% dichlorodifiuoromethane, the total volatile matter content again being about 55%. Hence, it will be understood that all products lying on and above the line 13-20 contain by weight a total volatile matter content of 1,1,1- difluorochloroethane and dichlorodifluoromethane of not less than about 55%. Similarly, as before stated in connection with the specific product denoted at I8, all products on-and above line i3-20 have a total volatile matter content up to about 95% by weight. All of the products of this group have vapor pressures at 70 F. in the range of about 23-24 to about 40 p. s. i. g.

In some circumstances it is preferable to employ higher minimum amounts of 1,1,1-difiuorochloroethane, desirably in the weight range of 30-76%. In this instance, where it is desired to formulate products having a total volatile matter content in the range of about 40-95%, and provide compositions having a vapor pressure in the range of about 18-19 to 40 p. s. i. g. at 70 F., the appropriate dichlorodifiuoromethane range is changed to a maximum of about 38% and, as the 1,1,1-difluorochloroethane contentv increases to about 76%, the dichlorodifluoromethane content 6 decreases progressively to about 5%. Hence, the particular product at 22 contains by weight about 30% 1,1,l-difluorochloroethane and about 38% dichlorodifiuoromethane, total volatile matter content being about 68%. The specific product at I 6 contains about 30% 1,1,1-difiuorochloroethane and about 10% dichlorodifluoromethane, the total volatile matter content being about 40%. In the case of products of compositions presently under discussion, i. e. those lying within the area bounded by straight lines connecting points 22I6i2-ll-i822, it will be noted that all such products lying above line l2-I6-l| have total volatile matter contents of about 40% or more and, similarly as stated in previous discussion with reference to point 18, a maximum volatile matter content of about 95% by weight.

' tile matter.

Furthenall such products lie within the boundaries of vertical line l2-I1, and the vertical line passing thru point 22 which denotes. a dichlorodifluoromethane content of about 38%. Hence, all products of the type now being described have a. dichlorodifluo-romethane content in the range of 38-5% by weight.

In some cases, it may be desirable to form products similar to those discussed just above and 'having a 1,1,1-difiuorochloroethane content in the 15-76% range but having a, minimum total voltatile matter content of not less than by weight. Thus, the product at IU contains about 15% difluorochloroethane and about 45% difluorodichloromethane, and the product at 25 contains about 30% 1,l,l difluorochloroethane and about 30% dichlorodifluoromethane, each product having a total volatile matter content of about 60%. The particular product at 26 contains about 50% 1,1,l-difluorochloroethane and about 10% dichlorodifiuoromethane, a total volatile Accordingly, all products lying on and above the line Ill-21 contain not less than about 60% by weight of vola- The products in this group have vapor pressures at F. in the range of the order of 25-26 to about 40 p. s.-i. g., contain about 15% to about 76% 1,1,l-difiuorochloroethane, about 45% to about 5% dichlorodifluoromethane, have a total volatile matter content of 1,1,1-difluorochloroethane and dichlorodifiuoromethane of not less than about 60% and not more than about 95% by weight, and lie within the area denoted by the lines I025-2621l1l8-|0.

A preferred group of products, similar to those discussed just above, have a 1,1,1-difiuorochloroethane content of about 50 and more up to about 76%, and have a minimum volatile matter content of not less than 60% by weight. Thus, the

, product at I l contains about 50% 1,1,1-difluoromatter content of about 60%.

chloroethane and about 30% dichlorodifluoromethane, a total volatile matter content of about The particular product at 20 contains about 50% 1,1,1-difluorochloroethane and about 10% dichlorodifiuoromethane, a total volatile The product at 21 contains about 55% difiuorochloroethane and about 5% difiuorodichloromethane. As above by weight of volatile matter. The products of this particularly preferred group have vapor pressures at 70 F. in the range of the order of 25-26 to about 40 p. s. i. g., contain about 50% to about 76% 1.1,1-difiuorochloroethane, about 30% to about 5% dichlorodifluoromethane. have a total volatile matter content of 1,1,1-difiuorochloroethane and dichlorodifluoromethane of not about. 40-25% trichlorofluoromethane.

r-less than about 60% and not more than about 5.95% by weight, and lie within the area denoted mately at 28.

A further preferred group of products, having a high 1,1,1-difluorochloroethane content, have a vapor pressure in the range of about 26 to about 37 p. s. i. g. at 70 F. and contain about 50% by weight of 1,1,1-difiuorochloroethane. The particular product denoted at 25 contains about 50% v 1,1,l-difiuorochloroethane and about 10% dichlorodifiuoromethane, has a total volatile matter content'of about 60%, and a, vapor pressure of the order of 26-27 p. s. i. g. at 70 F. Similarly,

..the specific product indicated at about 40 has a vapor pressure of the order of 36-37 p. s. i. g. at

70 F., contains about 50% 1,1,1-difiuorochloroethane and about dichlorodifluoromethane,

a total volatile matter content of about 75%. The products of this preferred group all lie on that portion of diagonal line 5 within the approximate points designated by 26 and 40. Hence, I all such products have-a vapor pressure in the -.r.ange of about 26 to about 37 p. s. i. g. at 70 F.,

contain about 50% 1,1,1-difiuorochloroethane, about 10-25% dichlorodifluoromethane, and Further, these compositions have a total volatile matter content of 1,1,1-difiuorochloroethane and dichlorodifiuoromethane not less than about 60% and not more than about 75% by weight.

One specific preferred product of the immediately foregoing group has a vapor pressure of about 26-27 p. s. i. g. at 70 F., contains about 50% 1,1,1-difiuorochloroethane, about 10% dichlorodifluoromethane and about 40% trichlorofiuoromethane, this material having a total volale matter content of 1,1,1-difluorochloroethane and dichlorodifluoromethane of about 60% by weight. Such a product is indicated on the chart approximately at 26. Another preferred specific product of this group has a vapor pressure of about 30-37 p. s. i. g. at 70 F., contains about 50% 1,1,1-difiuorochloroethane, about 25% dichlorodifluoromethane, and about 25% trichlorofiuoromethane. This product has a total volatile matter content of 1,1,1-difluorochloroethane and dichlorodifluoromethane of about 75% by weight, and such product is indicated on the chart approximately at 40.

In other situations, it is preferable to form products having vapor pressure in the range of about 31 to about 40 p. s. i. g. at 70 F., and containing 1,1,1-difluoroch1oroethane in the range of about 15% to about 76% by weight. The prodduct at if] contains about 15% by weight of 1,1,1- difluorochloroethane, and about 45% of dichlorodifluoromethane. a total volatile matter content of about 60%. The particular product at contains about 15% 1,1,1-difluorochloroethane and about 32% dichlorodifiuoromethane, i. e. total volatile matter of about 47%, and the product at 11 contains about 76% 1,1,1-difluorochloroethane and about 5% dichlorodifiuoromethane, a total .of 81 volatile matter. Hence, all products above line 35-41 contain not less than about 47% total volatile matter. It will be seen that this instantly discussed group of products, lying in the area of lines l035ll--l8-l0, all contain about 15- 76% 1,1,1-difiuorochloroethane, about 47-5% dichlorodifiuoromethane, and have a total volatile matter content of not less than about 47% and not more than about by weight.

Other formulations falling within the scope of the invention are as follows.

Improved dispersant compositions may contain by weight not less than above 15% and up to about 50% of 1,1,1-difluorochloroethane, not more than 45% and down to about 5% of di- .chlorodifiuoromethane, the remainder, to provide a composition, being trichlorofluoromethane.

Such compositions may be diagrammatically denoted as lying substantially within the area bounded by the straight lines connecting the points i0i il2l3i4l0. A11 compositions between line I and just short of line 5 contain 1,1,1-difiuorochloroethane in amount ranging from about 15% up to about 50% by weight, and all such compositions lying to the left of the vertical passing thru the i0 and to the right of vertical line !2l3 contain dichlorodifiuoromethane in the range of about 45% .down to about 5% by weight. As previously noted, all compositions lying on and above line i|l2 contain not less than about 40% by weight of volatile matter. The particular composition slightly to the right of i5 contains just short of 50 1,1,1-difluorochloroethane and a little more than 30% dichlorodifiuoromethane, and accordingly has a volatile matter content a little less than 80%. As shown, all of the products of this group have vapor pressures at 70 F. in the range of about 58-19 to about 40 p. s. i. g.

As previously explained, all products lying on and above line 20-l3 have a total volatile matter content of about 55% or more. Hence, products lying substantially Within the area bounded by the lines l020l 3-l ii! 0 contain by weight about 15% up to just short of 50% 1,1,1-difluorochloroethane, about 45% down to about 5% dichlorodifiuoromethane, have a total volatile matter content of 1,1,l difluorochloroethane and dichlorodifluoromethane of not less than about 55 and up to about 80% by weight, and have vapor pressures at 70 F. in the range of about 23-24 to about 40 p. s. i; g. Further, as noted above, all products lying on and above line !02 520 have a total volatile matter content of about 60% or more. Hence, products lying substantially within the area bounded by the lines i02 5-26l tl0 contain by weight about 15% up to about 50% 1,1,1-difiuorochloroethane, about 45% down to a little more than 10% dichlorodifiuoromethane, have a total volatile matter content of 1,1,l-difluorochloroethane and dichlorodifiuoromethane of not less than about 60% and up to about 80% by weight, and have vapor pressures at 70% in the range of about 2627 to about 40 p. s. i. g.

In other situations, it may be desirable to form products having vapor pressure in the range of about 30 to about 40 p. s. i. g. at 70 F., and containing 1,1,1-difiuorochloroethane in the range of about 15% up to about 50% by weight. As above noted, the specific product at i0 contains about 15% by weight of 1,1,l-difluorochloroethane, and about 45% of dichlorodifiuoromethane, a total volatile matter content of about 60%. The particular product at 32 contains about 15% 1,1,1- difluorochloroethane and about 30% dichlorodifluoromethane, i. e. total volatile matter of about 45%, and the product at about 33 contains just short of 50% 1,1,l-difiuorochloroethane and a little more than 15% dichlorodifiuoromethane, a total of a little less than 65% volatile matter. Hence, all products on and above line 3233 contain not less than about 45% total volatile matter. It will be seen that this'instantly discussed group of products, lying substantially in the area of lines I3233MI0,.;all contain about 15% up to about 50% 1,1,1-difluorochloroethane, about 45% down to about 15% dichlorodifiuoromethane, and have a total volatile matter content of not less than about 45% and up to about 80% by weight.

Diagonal line 45 on the drawing represents the composition-vapor pressure at 70 F. relationship of various prior art mixtures of dichlorodifluoromethane and trichlorofiuoromethane. A comparison of diagonal line 45 with any of lines I, 2, 3, 4, or 6 shows that the incorporation into a mixture of dichlorodifiuoromethane and trichlorofiuoromethane of any amount of 1,1,1-difluorochloroethane provides a low pressure dispersant'which has, for any given or required 70 F. vapor pressure, a higher volatile matter content than the volatile matter content of mixtures of dichlorodifluoromethane and trichlorofluoromethane having the same 7 0 F. vapor pressure value. Hence, at a 70 F. vapor pressure of about 25 p. s. i. g., a dichlorodifiuoromethane trichlorofiuoromethane mixture has a volatile matter content (dichlorodifiuoromethane) of about 35%. At the same vapor pressure, a product of the invention containing for example 30% 1,1,l-difluorochloroethane (diagonal line 3 on the drawing) contains approximately dichlorodifluoromethane, and consequently has a total volatile matter content of 45%, as compared with the 35% value of the dichlorodifluoromethanetrichlorofiuoromethane mixture. At the same vapor pressure, a product of the invention containing about 50%, 1,l,1-difluorochloroethane contains about 7% dichlorofluoromethane, and hence has a total volatile matter content of about 57% as compared with the 35% value of the dichlorodifluoromethane triohlorofiuoromethane mixture. At a 70 F. vapor pressure of about 35 p. s. i. g., a mixture of dichlorodifluoromethane and trichlorofiuoromethane contains about 50 by Weight of dichlorodifluoromethane and hence a volatile matter content of about 50% by weight. At the same vapor pressure, the 30% 1,1,1-difluorochloroethane composition of the invention (diagonal line 3 on the drawing) contains about 31% dichlorodifiuoromethane, and consequently has a total volatile matter content of about 61% At a 70 F. vapor pressure of about 38 p. s. i. g., the 76% 1,1,1-difiuorochloroethane product of the invention (diagonal line 6 on the drawing) contains about 16% dichlorodifluoromethane, has a total volatile matter content of about 92%, the total volatile matter content of the dichlorodifluoromethane triohlorofluoromethane mixture of the same pressure being less than about 55%. A further advantage applicable to all products of the invention, arising from the incorporation of 1,1,1-difiuorochloroethane is that in view of its low specific gravity, mixtures containing the same possess relatively large volumes per given weight as compared with the volumes of mixtures of dichlorodifiuoromethane and. trichlorofluoromethane which do not contain any of the 1,1,1- difiuorochloroethane.

This application is a continuation-in-part of 10' my U. S. application Serial No. 793,418, filed December 23, 1947, now abandoned.

I claim:

1. A non-flammable, non-toxic liquid composition, adaptedfor use as a dispersant, having a vapor pressure in therange .of about 18 to about 40 pcs. i. g. at 70 F., and consisting of 1,1,l-difiuorochloroethane, dichlorodifiuoromethane, and trichlorofluoromethane; said composition containing by weight about 15% to about 76% l,l,l-difiuorochloroethane, about to about 5% dichlorodifluoromethane, the remainder being trichlorofiuoromethane; the amounts of 1,1,l-difluorochloroethane and dichiorodifluoromethane bein such that said composition has a total volatile matter content of 1,1,1-difluorochloroethane and dichlorodifluoromethane of not less than about 40% and not more than about 95% by weight, said composition being maintained under sufiicient pressure in a confined space to keep it in the liquid phase.

2. A non-flammable, non-toxic liquid composition, adapted for use as a dispersant, having a vapor pressure in the range of about 23 to about 40 p. s. i. g. at 70 F., and consisting of 1,1,1- difluorochloroethane, dichlorodifluoromethane, and trichlorofluoromethane; said composition containing by weight about 15% to about 76% 1,1,l-difluorochloroethane, about 45% to about 5% dichlorodifiuoromethane, the remainder being trichlorofluoromethane; the amounts of 1,1,1-

difiuorochloroetharie and dichlorodifluoromethane being such that said composition has a total volatile matter content of 1,1,1-difluorochloroethane and dichlorodifluoromethane of not less than about and not more than about 95% by weight, said composition being maintained under sufficient pressure in a confined space to keep it in the liquid phase.

3. A non-flammable, non-toxic liquid composition, adapted for use as a dispersant, having a vapor pressure in the range of about 25 to about 40 p. s. i. g. at 70 F'., and consisting of 1,1,1- difluorochloroethane, dichlorodifiuoromethane, and trichlorofiuoromethane; said composition contained by weight about 50 to about 76% 1,1,1- difiuorochloroethane, about 30% to about 5% dichlorodifiuoromethane, the remainder being trichlorofluoromethane; the amounts of 1,1,l-difluorochloroethane and dichlorodifluoromethane being such that said composition has a total volatile matter content of l,1,1-difiuorochloroethane and dichlorodifluoromethane of not less than about and not more than about 95% by weight, said composition being maintained under sufiicient pressure in a confinedspace to keep it in the liquid phase.

4. A non-flammable, non-toxic liquid composition, adapted for use as a dispersant, having a vapor pressure in the range of about 18 to about 40 p. s. i. g. at R, and consisting of 1,1,1- difluorochloroethane, dichlorodifiuoromethane, and trichlorofiuoromethane; said composition containing by weight about 15% up to about 50% 1,1,1-difiuorochloroethane, about 45% down to about 5% dichlorodifluoromethane, the remainder being trichlorofiuoromethane; the amounts of 1,1,1-difiuorochloroethane and dichlorodifiuoromethane being such that said composition has a total volatile matter content of 1,1,l-difluorochloroethane and dichlorodifluoromethane of not less than about 40% and up to about 80% by weight, said composition being maintained under sufficient pressure in a confined space to keep it in the liquid phase.

5. A non-flammable, non-toxic liquid compo-' sition, adapted for use as a dispersant, having a vapor pressure in, the range of about 28 to about 3'7 p. s. i; g. at 70 F., and consisting of 1,1,1-difluorochloroethane, dichlorodifluoromethane, and trichlorofluoromethane; said composition containing by Weight about 50% 1,1,1-difluorochloroethane, about to about dichlorodifluoromethane, and about to about 25% trichlorofiuoromethane; the amounts of 1,1,l-difluorochloroethane and dichlorodifluoromethane being such that said composition has a total volatile matter content of 1,1,l-difluoro chloroethane and dichlorodifiuoromethane of not less than about 60% and not more than about 75% by weight, said composition being maintained under sulficient pressure in a confined space to keep it in the liquid phase.

6. A non-flammable, non-toxic liquid compo sition, adapted for use as a dispersant, having a vapor pressure in the range of about 25-27 p. s. i. g. at 70 11, and consisting'of 1,1,1-difluorochloroethane, dichlorodifluoromethane, and trichlorofiuoromethane; said composition containing by weight about 1,1,1-difluorochloroethane, about 10% dichlorodifiuoromethane, and about 40% trichlorofluoromethane; the said composition having a total volatile matter content of 1,1,1-difiuorochloroethane and dichlorodifluoromethane of about by Weight and being maintained under suiiicient pressure in a confined space to keep it in the liquid phase.

7. A non-flammable, non-toxic liquid composition, adapted for use as a dispersant, having a vapor pressure in the range of about 238F237 p. s. i. g. at F., and consisting of 1,1,1-difluorochloroethane, dichlorodifiuoromethane, and trichlorofiuoromethane; said composition containing by weight about 50% 1,1,1-difluorochloroethane, about 25% dichlorodifluoromethane, and

about 25% trichlorofiuoromethane; the said composition having a total volatile matter content of 1,1,l-difluorochloroethane and dichlorodifiuoromethane of about by weight and being maintained under sufiicient pressure in a confined space to keep it in the liquid phase.

8. A non-flammable, non-toxic'liquid composition, adapted for use as a dispersant, having a vapor pressure in the range of about 38-39 p. s. i. g. at 70 F., and consisting of 1,1,1-difluorochloroethane, dichlorodifiuoromethane, and trichlorofluoromethane; said composition containing by weight about 76% 1,1,l-difiuorochloroethane, about 16% clichlorodifiuoromethane, and about 8% trichlorofiuoromethane; the said composition having a total volatile matter content of 1,1,l-difiuoroc-hloroethane and dichlorodifluoromethane of about 92% by weight and being maintained under sufficient pressure in a confined space to keep it in the liquid phase.

FREDERICK G. LODES.

REFERENCES CITED The following references are of record in the file of this patent:

Journal Am. Chem. Soc, June 1936, pp. 889 and 890.

Soap and Sanitary Chemicals, April 1945, vol. 21, No. 4, pp. 123, and 127.

Committee of Medical Research of the Ofiice of Sci ntific Research and Development Bimonthly Progress Report No. 25, Section. 2, period ending August 31, 1945, available from Office of Technical Services, Aug. 12, 1946, subject: Research on Insects Affecting the Armed Forces, Contract No. OEMcmr-M-433l, page 3.

Soap and Sanitary Chemicals, Dec. 1946, vol. 22, pp 137. 

1. A NON-FLAMMABLE, NON-TOXIC LIQUID COMPOSITION, ADAPTED FOR USE AS A DISPERSANT, HAVING A VAPOR PRESSURE IN THE RANGE OF ABOUT 18 TO ABOUT 40 P. S. I. G. AT 70*F., AND CONSISTING OF 1,1,1-DIFLUOROCHLOROETHANE, DICHLORODIFLUOROMETHANE, AND TRICHLOROFLUOROMETHANE; SAID COMPOSITION CONTAINING BY WEIGHT ABOUT 15% TO ABOUT 76% 1,1,1-DIFLUOROCHLOROETHANE, ABOUT 45% TO ABOUT 5% DICHLORODIFLUOROMETHANE, THE REMAINDER BEING TRICHLOROFLUOROMETHANE; THE AMOUNTS OF 1,1,1-DIFLUOROCHLOROETHANE AND DICHLORODIFLUOROMETHANE BEING SUCH THAT SAID COMPOSITION HAS A TOTAL VOLATILE MATTER CONTENT OF 1,1,1-DIFLUOROCHLOROETHANE AND DICHLORODIFLUOROMETHANE OF NOT LESS THAN ABOUT 40% AND NOT MORE THAN ABOUT 95% BY WEIGHT, SAID COMPOSITION BEING MAINTAINED UNDER SUFFICIENT PRESSURE IN A CONFINED SPACE TO KEEP IT IN THE LIQUID PHASE. 